T EC H N I CAL
Surge anticipating valves: help or hindrance? By Johan Cilliers, Valve Product Manager, Amiad Water Systems.
Surge anticipating valves (SAVs) offer relatively low maintenance, low cost, and small footprint compared to other surge protection alternatives, but there is a reluctance to use surge anticipating valves by many end users and pump providers, frustrated by the valves “not working”.
S
AVs play an essential safety role for pumped systems where there is a risk that the system could suffer from the destructive force of water hammer caused by a sudden pump stop. Slow release (“anti-slam” or “non-slam”) air valves are also effective in assisting
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with the surge mitigation in conjunction with SAVs. If the (unprotected) example system experiences a sudden pump stop, a surge pattern with extreme pressures can be generated when the
kinetic energy of the returning flow is converted to potential (pressure) energy, oscillating along the pipeline. The time it takes for this pressure surge to travel to the end of the pipe and back (TC) can be calculated if →
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